Speaking to IncGamers,
No matter what the case, however, Mass Effect 3 signals the end of Commander Shepard’s story. But there are many more stories that could be told:
“This is the end of Shepard’s story,” said Gamble, “but we’ve developed too big of an IP for us to conclusively say that there will never be another Mass Effect – there are just too many stories that we could potentially tell. But it definitely wouldn’t be Shepard’s story if there was to be another game.”
Gamble refused to comment further when we asked him whether or not the developer would always keep the franchise as an RPG. We tried to push him on whether they would be happy to see the IP taken in a new direction by another developer (in a similar manner to Halo Wars, perhaps) but he wouldn’t budge.
For more Mass Effect 3 info you’ll want to check out our of the game’s opening 90 minutes.